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DOE OSTI · 2584695

C-C Coupling Mechanism on Cu(100) A Molecular Dynamics Study at 298K

Yang, Timothy [Oak Ridge Institute for Science and Education (ORISE)]·Saidi, Wissam [NETL] (ORCID:0000000167144832)
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Abstract

The electrochemical reduction of carbon dioxide (CO2) into valuable fuels such as C1 (syngas, methane) and C2 (ethylene, ethanol) products is a key strategy for achieving a carbon-neutral economy. Computational studies of C-C coupling, a critical step in CO2 reduction, are essential for designing more efficient catalysts. However, simulating these processes under realistic electrochemical conditions, including temperature and solvent effects, is computationally demanding. In this work, we develop a machine learning-based atomistic potential to study CO2 reduction on Cu(100) surfaces, accounting for temperature and explicit water solvent effects. We compute thermodynamic free energies of the possible C-C coupling pathways, CO*+CO*→OCCO*, CO*+CHO*→OCCHO*, CO*+COH*→OCCOH*, CHO*+COH*→OHCCOH*, COH*-COH*→HOCCOH*, and CHO*-CHO*→OHCCHO*. Our results quantify the thermodynamic tendencies of these reactions and reveal that, in addition to the well-established CO* + CO* → OCCO* pathway, CHO* is a critical intermediate in the formation of C2 products on Cu(100). Furthermore, we demonstrate that the machine learning approach offers a cost-efficient framework for studying CO2 reduction on diverse catalysts under realistic electrochemical conditions.

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Yang, Timothy [Oak Ridge Institute for Science and Education (ORISE)], Saidi, Wissam [NETL] (ORCID:0000000167144832). 2025-03-27. C-C Coupling Mechanism on Cu(100) A Molecular Dynamics Study at 298K. https://doi.org/10.2172/2584695

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